SAN LUIS OBISPO (CN) - Environmentalists asked a federal judge to shut down California's last nuclear power plant, claiming the Nuclear Regulatory Commission has failed to show the 40-year-old Diablo Canyon Power Plant can withstand a significant earthquake from a fault discovered in 2008.
But PG&E, the energy company that owns the plant in San Luis Obispo County, said it has thoroughly examined the plant and that it could withstand an earthquake from the biggest fault line in the area.
Friends of the Earth, which helped shut down a nuclear plant in San Onofre last year, filed a petition for review on Oct. 28 against the U.S. Nuclear Regulatory Commission, in the U.S. Court of Appeals for the District of Columbia.
Friends of the Earth claims the NRC has underestimated the Shoreline Fault and allowed PG&E to make significant changes to its Diablo Canyon safety report without a required public hearing.
Even before construction began on the plant in 1968, there were concerns about nearby fault lines. Concerns have been heightened with the discovery of new ones.
"You now have a web of faults that are far larger than they had any idea about when they designed and licensed the plant," said Damon Moglen, senior strategic advisor for Friends of the Earth, which was founded to oppose Diablo in 1969.
"This plant is arguably the most at-risk plant in America."
The group asked the court to review the NRC's approval of the Diablo safety report; to declare that the NRC violated the law by not holding a public hearing when changes were made to the report; to compel the NRC to hold public hearings; and to shut down the plant until those hearings are complete.
Lara Uselding, a spokeswoman for the NRC, said the regulatory agency was not yet prepared to offer a response to the new suit.
PG&E said the Friends of the Earth mischaracterized the facts on seismic safety at Diablo Canyon.
"PG&E followed the NRC's regulatory process regarding our analysis of the Shoreline Fault and as new and unprecedented research has demonstrated, the facility can withstand the largest tremors that the Shoreline and other faults in the region can produce," spokesperson Blair Jones said in an email.
Two women were killed in San Luis Obispo County in a 6.5 magnitude quake in 2003.
When the Hosgri Fault was discovered in 1973, the NRC forced PG&E to make substantial modifications to the plant, ensuring it could properly shut down in the event of a magnitude-7.5 earthquake.
Thirty-five years later, PG&E discovered the Shoreline Fault, which it reported to the NRC. PG&E requested an amendment to the Diablo safety report, so it could include information about the Shoreline Fault. Such an amendment would require public hearings.
But the NRC allowed PG&E to work around the amendment by including the Shoreline Fault in safety considerations tailored to the Hosgri Fault, saying the Shoreline Fault was deemed to be less powerful than the Hosgri Fault. PG&E agreed and withdrew its request.
"No fault in the area exceeds the Hosgri design," Jones said.
In 2013, NRC employee Michael Peck, a former senior resident inspector at the plant, filed a different professional opinion, criticizing the NRC's review of the Shoreline Fault, which runs just offshore of the plant.
Saying pipes and other important equipment might not be able to withstand the maximum shaking the Shoreline Fault might generate, Peck recommended the plant be shut down until that concern could be disproved.
"The new seismic information resulted in a condition outside the bounds of the existing Diablo Canyon design basis and safety analysis," Peck wrote. "Continued reactor operation outside the bounds of the NRC approved safety analyses challenges the presumption of nuclear safety."
The NRC convened an independent review panel to look at Peck's allegations, and NRC's executive director of operations, Mark Satorious, met with Peck to hear his concerns.
In a memo to Peck, Sartorious said there were no immediate seismic issues at the plant.
"A compelling basis for my conclusion is drawn from our meeting on July 30, 2014, when you and I agreed that there is not now nor has there been an immediate or significant safety concern associated with this Diablo Canyon issue," Sartorious wrote.
The Friends of the Earth contend the Shoreline Fault is larger than what PG&E is claiming. And it says the latest safety analysis report had been changed with a new method for measuring seismic safety.
The relationship between the NRC and PG&E, Moglen said, has become too cozy, and the NRC has allowed PG&E to put profit ahead of safety.
"This was all done behind closed doors, between the regulators and the regulatees," Moglen said. "I think these people have got to be held accountable."
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